Post on 23-Jan-2016
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RECAP OF PREVIOUS LECTURE
PHYSICAL COMPONENTS
• Lithosphere – rocks and
soils
• Hydrosphere – water
• Atmosphere - air
Exponential growth of human
population began in the 1800s
Human population growth rate in percent
Human population growth issue
China & Mexico and India face more environment stress with
the highest population
Population growth rates are high in poor areas, whereas
resources consumption and well-being are low
Factors human population growth:
a. Migration : the relocation of humans
b. Developments
c. Innovation in agriculture increased food supply
Managing population growth
a. Family planning
b. Development and population – economic development,
education
ENVIRONMENTAL PROBLEMS
Environmental Problem: POLLUTION
What is pollution?
Where does it come from?
• Any addition to air, water, soil, or food that threatens the
health, survival, or activities of humans or other living
organisms
• The particular chemical or form of energy that causes such
harm is called pollutant
• Most pollutants are solid, liquid, or gaseous by-products or
wastes produced when resource is extracted, processed,
made into products, or used
• Pollution can also take the form of unwanted energy
emissions, such as excessive heat, noise or radiation
Environmental Problem: SOIL POLLUTION
Defined as the build-up in soils of persistent toxic
compounds, chemical, salts, radioactive materials, or
disease causing agents, which have adverse effects on
human, plant growth, and animal health
• The wars the hit the Earth are one of the immediate
causes of soil pollution
• Many countries found the necessity to improve their
living standards
• After the WWII (1945), may countries suffered from food
shortage and this facilitated the introduction of fertilizers
and other agricultural chemicals
Environmental Problem: SOIL POLLUTION
Sources / Types of soil contamination
• Rupture of underground storage tanks (i.e. septic tanks,
etc.)
• Application of pesticides
• Percolation of contaminated surface water to subsurface
strata
• Oil and fuel dumping
• Leaching of wastes from landfills
• Direct discharge of industrial wastes to the soil
Environmental Problem: SOIL POLLUTION
Examples
• Pesticides such as DDT
(dichlorodiphenyltrichloroethane), a potent nerve poison
in insect was widely used to combat fever and malaria
• It was later used to control and/or eradicate disease
carrying and crop eating insects
• Effects: DDT prevents the shelling of bird eggs and in
human causes health threats
Environmental Problem: SOIL POLLUTION
Examples
• Arsenic, used by the glass industries is also a pollutant
(very poisonous)
• Arsenic are used to eliminate the green color caused
by impurities of iron compounds
• Other examples: heavy metals such as lead, iron,
chromium, copper, zinc – although small traces are
necessary for plant growth, high concentrations of
these compounds renders the land unsuitable for plant
growth
Environmental Problem: SOIL POLLUTION
Impacts of Soil Pollution
• Radical chemistry changes, manifested in the alteration
of metabolism of endemic microorganisms and
arthropods resident in a given soil environment
• Disruption of the food chain
• Alter plant metabolism, reducing crop yields
• More economic losses
Environmental Problem: WATER POLLUTION
Contamination of water bodies such as lakes, rivers, oceans,
and ground water by human activities
Environmental Problem: WATER POLLUTION
Categories of Water Pollution
Point source pollution – contaminants that enter a waterway
through a discrete conveyance, such as ditch or pipe (sewerage
treatment plant, factory, etc.)
Non-point source pollution – diffuse contamination that does not
originate from a single discrete source. It is often accumulative
effect of small amounts of contaminants gathered from a large area
Ground water pollution – groundwater contamination;
contamination of aquifers
Example: spill of chemical contamination of soil, located away from
a surface water body, may not necessarily create point source or
non-point source pollution, but nonetheless, may contaminate the
aquifer below
Environmental Problem: WATER POLLUTION
Causes of Water Pollution
Pathogens
• Coliform bacteria
• Cryptosporidium parvum
• Giardia lamblia
• Salmonella
• Novovirus and other viruses
• Parasitic worms (helminths)
Environmental Problem: WATER POLLUTION
Causes of Water Pollution
Chemicals and other contaminants
• Detergents
• Disinfection by-products found in chemically disinfected
drinking water, such as chloroform
• Food processing waste (i.e. fats and greases)
• Insecticides and herbicides
• Petroleum hydrocarbons (i.e. gasoline, diesel fuel, jet fuels,
fuel oil)
• Lubricants (motor oil)
• Chemical waste industrial by-products
Environmental Problem: WATER POLLUTION
Causes of Water Pollution
Chemicals and other contaminants
• Fuel combustion by-products
• Tree and bush debris from logging operations
• Volatile organic compounds (industrial solvents, chlorinated
solvents
• Acidity caused by industrial discharges (sulfur dioxide from
power plants)
• Ammonia from food processing waste
• Chemical waste industrial by-products
• Fertilizers containing nitrates and phosphates
• Heavy metals
• Silt (sediment) in runoff from construction sites, logging,
slash and burn practices or land clearing sites
Environmental Problem: WATER POLLUTION
Causes of Water Pollution
Macroscopic pollution
• Large visible items polluting waters (marine debris)
• Trash (i.e. paper, plastic, food waste)
• Nurdles (small ubiquitous waterborne pellets)
• shipwrecks
Environmental Problem: WATER POLLUTION
Causes of Water Pollution
Thermal pollution
• Rise or fall in the temperature of a natural body of water
caused by human influence
• Common cause: use of water as a coolant by power plants
and industrial manufacturers
• Also caused by the release of very cold water from the
base of reservoirs into warm rivers
Environmental Problem: WATER POLLUTION
Impacts of Water Pollution
• Unsuitable for human consumption
• Can cause diseases (i.e. cholera, typhoid, gastroenteritis,
diarrhea, parasitic infection)
• Corrosion potential of water
• Problematic for certain irrigated crops, reduced crop
yields
• Affects biodiversity (i.e. aquatic organisms, birds feeding
on aquatic animals)
• Blockage of drains, overflowing sewerage systems
Environmental Problem: AIR POLLUTION
Introduction of chemicals, particulate matter, or biological
materials that cause harm or discomfort to humans or other living
organisms, or damages natural atmosphere, into the atmosphere
Environmental Problem: AIR POLLUTION
Most common air pollutants in the air
Sulfur oxides (SOx) – e.g. sulfur dioxide (SO2-; SO2)
Anthropogenic sources: industrial processes,
combustion of coal and petroleum
Natural sources: volcanic eruption
Effects: combined with NO2 will cause acid rain
(H2SO4)
Nitrogen oxides (NOx) – e.g. nitrogen dioxide (NO2);
the most prominent air pollutant; reddish-brown toxic
gas that has a sharp, biting odor
Anthropogenic sources: high temperature
combustion
Environmental Problem: AIR POLLUTION
Most common air pollutants in the air
Carbon dioxide (CO2) – (vital to living organisms)
Anthropogenic sources: combustion
Natural sources: plants and animals (natural gas in
the atmosphere)
Carbon monoxide (CO)
colourless, odourless, non-irritating but very
poisonous gas
Anthropogenic sources: combustion
Natural sources: by-products of plant’s chemical
processes
Environmental Problem: AIR POLLUTION
Most common air pollutants in the air
Volatile organic compounds – e.g. methane (CH4),
benzene, tuolene, xylene
Anthropogenic sources: combustion, industrial
processes
Natural sources: plants and animals
Chlorofluorocarbons (CFCs)
harmfil to the ozone layer
Anthropogenic sources: industries (aerosol
propellants, cleaning solvents; refrigerants; plastic
blowing agents, etc.)
Environmental Problem: AIR POLLUTION
Most common air pollutants in the air
Ammonia – NH3-; gas with a pungent odor
Anthropogenic sources: pharmaceutical industries
Natural sources: agricultural processes (use of
fertilizers)
Environmental Problem: AIR POLLUTION
Impacts of Air Pollution
Human health - breathing/respiratory diseases
(emphysema, bronchitis), inflammation of epithelial
linings, long-term exposure causes cancer, asthma,
respiratory infections, pulmonary disease, cardiovascular
disease
Environmental – global warming and climate change
EXAMPLE OF WORLD’S WORST CASE INCIDENT/DISASTER
THE GREAT SMOG OF 1952 - December 1952, London
• To cope up with the very cold winter, Londoners burned more coal than usual
• The resulting air pollution was trapped by the inversion layer formed by the dense
mass of cold air, thereby increasing the concentrations of pollutants dramatically
• Fog was so thick, driving became almost impossible
• Decreased visibility resulted to more crimes
• During the 4-day period of fog, at least 4,000 died as a direct result of the weather
EXAMPLE OF WORLD’S WORST CASE INCIDENT/DISASTER
MALAYSIA’S HAZE PROBLEM 1997-98
• Cause: Forest fire in Sumatra, Indonesia, (manmade, to clear forest for oil palm
plantation?)
• The haze formed when sulphides, nitrous oxides, and ash released by burning are
combined with the industrial pollution and exhaust from cities
• Pollution index = 500 (first time in Malaysia); 200,000 people were hospitalized
• Affected other countries in the region = $9.3 B economic losses